DATA_QUALITY_INFORMATION

Attribute_Accuracy: Attribute_Accuracy_Report:
100 percent of attribute codes were reviewed against the
source manuscripts. No formal effort was undertaken to
develop a quantitative attribute accuracy statement.
Logical_Consistency_Report:
All data were found to be topologically correct. No
duplicate features are present. All areas are completely
described as depicted on the source manuscripts. No
undershoots or overshoots are present. All data were
consistently captured using the rules described in the
narrative associated with the Data Quality Table and in the
various feature table narrative files present at the
coverage level within the library.
Completeness_Report:
100 percent of features depicted on the ONC source
materials have been captured. 100 percent of the features
have valid attribute codes assigned to them.
Positional_Accuracy: Horizontal_Positional_Accuracy: Horizontal_Positional_Accuracy_Report:
The Horizontal Positional Accuracy Value represents overall
accuracy. Source chart-specific accuracies are available as
area feature attributes in the VMap-0 data quality
coverage. The primary accuracy analysis was performed on
one chart only in the prototyping phase of the DCW project.
Horizontal Positional Accuracy is expressed in meters.
Detailed horzontal accuracy figures were developed by
comparing the positions of well-defined points in the
roads, railroads, utility lines, and drainage coverages
against sources of higher accuracy, measuring the offsets,
and expressing differences as a Circular Map Accuracy
figure at a 90% confidence interval. This figure was
independently verified by adding known production errors to
source chart accuracies in a root sum square calculation.
Vertical_Positional_Accuracy: Vertical_Positional_Accuracy_Report:
This figure represents overall accuracy. Source
chart-specific accuracies are available as area feature
attributes in the V-Map 0 data quality coverage.
Vertical Positional Accuracy is expressed in meters.
Vertical accuracy figures were developed by comparing
elevation contour locations on 1:24,000 scale maps to
elevation values at the same location within the digital
database. Some manual interpolation was necessary to
complete this test. The analysis results are expressed as
linear error at a 90% confidence interval.
Lineage: Source_Information: Source_Citation: Citation_Information: Originator: National Imagery and Mapping Agency
Publication_Date: 1994
Title: Operational Navigational Chart
Edition: Geospatial_Data_Presentation_Form: map
Publication_Information: Publication_Place: St. Louis, MO
Publisher: National Imagery and Mapping Agency
Other_Citation_Details: Online_Linkage: Larger_Work_Citation: Citation_Information: Originator: Publication_Date: Title: Publication_Information: Publication_Place: Publisher: Online_Linkage: Source_Scale_Denominator: 1,000,000
Type_of_Source_Media: stable-base material
Source_Time_Period_of_Content: Time_Period_Information: Range_of_Dates/Times: Beginning_Date: 1974
Ending_Date: 1994
Source_Currentness_Reference: Publication dates
Source_Citation_Abbreviation: ONC
Source_Contribution:
All information found on the source with the exception of
aeronautical data
Process_Step: Process_Description: Source_Used_Citation_Abbreviation: Process_Date: 199404
Source_Produced_Citation_Abbreviation: Process_Contact: Contact_Information: Contact_Person_Primary: Contact_Organization: Geonex
Contact_Person: Contact_Position: Contact_Address: Address_Type: mailing and physical address
Address: 8950 North 9th Ave.
City: St. Petersburg
State_or_Province: FL
Postal_Code: 33702
Country: USA
Contact_Voice_Telephone: 813-578-0100
Contact_Facsimile_Telephone: 813-577-6946
Contact_Electronic_Mail_Address: Hours_of_Service:Top

ENTITY_AND_ATTRIBUTE_INFORMATION

Overview_Description: Entity_and_Attribute_Overview:
The DCW used a product-specific attribute coding system
that is composed of TYPE and STATUS designators for area,
line, and point features; and LEVEL and SYMBOL designators
for text features. The TYPE attribute specifies what the
feature is, while the STATUS attribute spedcifies the
current condition of the feature. Some features require
both a TYPE and STATUS code to uniquely identify their
characteristics. In order to uniquely identify each
geographic attribute in the DCW, the TYPE and STATUS
attribute code names are preceded by the two letter
coverage abbreviation and a two letter abbreviation for the
type of graphic primitive present. VMap-0 data is attribute
coded in accordanced with Feature and Attribute Coding
Catalog (FACC). The DCW Type/Status codes were mapped into
the FACC coding scheme. A full description of FACC may be
found in Digital Geographic Information Exchange Standard
Edition 1.2, January 1994.
Entity_and_Attribute_Detail_Citation:
Entities (features) and Attributes for DCW are fully
described in: Department of Defense, 1992, Military
Specification Digital Chart of the World (MIL-D-89009):
Philadelphia, Department of Defense, Defense Printing
Service Detachment Office. VMap-0 is described in:
Department of Defense, Military Specification, Vector Map
(VMap) Level 0 (MIL-V-89039), 9 Feb 1995.
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